Document WO 2013/120956 A1 describes a method for measuring the uniform diffuse reflectance at least at one point of an object using a device comprising a means able to emit color illuminants expressed in the form of light flows and an electronic color image sensor, and a device comprising a means able to emit color illuminants in the form of light flows of colors and an electronic color image sensor, to measure the uniform diffuse reflectance at least at one point of an object placed in a zone located in the illumination field of said means able to emit colors and being located in the field of view of the electronic color image sensor and being subject to an outside illuminant in the form of a constant and unknown surrounding outside light flow.
To determine the reflectance of an object, it is known to use specialized high precision devices, such as diffraction spectrometers or double parallel photoreceptor spectrometers.
However, such devices are costly and difficult to use for nonspecialized operators.